Commit 503f82a9 authored by Luis Henriques's avatar Luis Henriques Committed by Ilya Dryomov

ceph: support copy_file_range file operation

This commit implements support for the copy_file_range syscall in cephfs.
It is implemented using the RADOS 'copy-from' operation, which allows to
do a remote object copy, without the need to download/upload data from/to
the OSDs.

Some manual copy may however be required if the source/destination file
offsets aren't object aligned or if the copy length is smaller than the
object size.
Signed-off-by: default avatarLuis Henriques <lhenriques@suse.com>
Reviewed-by: default avatar"Yan, Zheng" <zyan@redhat.com>
Signed-off-by: default avatarIlya Dryomov <idryomov@gmail.com>
parent 23ddf9be
// SPDX-License-Identifier: GPL-2.0 // SPDX-License-Identifier: GPL-2.0
#include <linux/ceph/ceph_debug.h> #include <linux/ceph/ceph_debug.h>
#include <linux/ceph/striper.h>
#include <linux/module.h> #include <linux/module.h>
#include <linux/sched.h> #include <linux/sched.h>
...@@ -1795,6 +1796,297 @@ static long ceph_fallocate(struct file *file, int mode, ...@@ -1795,6 +1796,297 @@ static long ceph_fallocate(struct file *file, int mode,
return ret; return ret;
} }
/*
* This function tries to get FILE_WR capabilities for dst_ci and FILE_RD for
* src_ci. Two attempts are made to obtain both caps, and an error is return if
* this fails; zero is returned on success.
*/
static int get_rd_wr_caps(struct ceph_inode_info *src_ci,
loff_t src_endoff, int *src_got,
struct ceph_inode_info *dst_ci,
loff_t dst_endoff, int *dst_got)
{
int ret = 0;
bool retrying = false;
retry_caps:
ret = ceph_get_caps(dst_ci, CEPH_CAP_FILE_WR, CEPH_CAP_FILE_BUFFER,
dst_endoff, dst_got, NULL);
if (ret < 0)
return ret;
/*
* Since we're already holding the FILE_WR capability for the dst file,
* we would risk a deadlock by using ceph_get_caps. Thus, we'll do some
* retry dance instead to try to get both capabilities.
*/
ret = ceph_try_get_caps(src_ci, CEPH_CAP_FILE_RD, CEPH_CAP_FILE_SHARED,
false, src_got);
if (ret <= 0) {
/* Start by dropping dst_ci caps and getting src_ci caps */
ceph_put_cap_refs(dst_ci, *dst_got);
if (retrying) {
if (!ret)
/* ceph_try_get_caps masks EAGAIN */
ret = -EAGAIN;
return ret;
}
ret = ceph_get_caps(src_ci, CEPH_CAP_FILE_RD,
CEPH_CAP_FILE_SHARED, src_endoff,
src_got, NULL);
if (ret < 0)
return ret;
/*... drop src_ci caps too, and retry */
ceph_put_cap_refs(src_ci, *src_got);
retrying = true;
goto retry_caps;
}
return ret;
}
static void put_rd_wr_caps(struct ceph_inode_info *src_ci, int src_got,
struct ceph_inode_info *dst_ci, int dst_got)
{
ceph_put_cap_refs(src_ci, src_got);
ceph_put_cap_refs(dst_ci, dst_got);
}
/*
* This function does several size-related checks, returning an error if:
* - source file is smaller than off+len
* - destination file size is not OK (inode_newsize_ok())
* - max bytes quotas is exceeded
*/
static int is_file_size_ok(struct inode *src_inode, struct inode *dst_inode,
loff_t src_off, loff_t dst_off, size_t len)
{
loff_t size, endoff;
size = i_size_read(src_inode);
/*
* Don't copy beyond source file EOF. Instead of simply setting length
* to (size - src_off), just drop to VFS default implementation, as the
* local i_size may be stale due to other clients writing to the source
* inode.
*/
if (src_off + len > size) {
dout("Copy beyond EOF (%llu + %zu > %llu)\n",
src_off, len, size);
return -EOPNOTSUPP;
}
size = i_size_read(dst_inode);
endoff = dst_off + len;
if (inode_newsize_ok(dst_inode, endoff))
return -EOPNOTSUPP;
if (ceph_quota_is_max_bytes_exceeded(dst_inode, endoff))
return -EDQUOT;
return 0;
}
static ssize_t ceph_copy_file_range(struct file *src_file, loff_t src_off,
struct file *dst_file, loff_t dst_off,
size_t len, unsigned int flags)
{
struct inode *src_inode = file_inode(src_file);
struct inode *dst_inode = file_inode(dst_file);
struct ceph_inode_info *src_ci = ceph_inode(src_inode);
struct ceph_inode_info *dst_ci = ceph_inode(dst_inode);
struct ceph_cap_flush *prealloc_cf;
struct ceph_object_locator src_oloc, dst_oloc;
struct ceph_object_id src_oid, dst_oid;
loff_t endoff = 0, size;
ssize_t ret = -EIO;
u64 src_objnum, dst_objnum, src_objoff, dst_objoff;
u32 src_objlen, dst_objlen, object_size;
int src_got = 0, dst_got = 0, err, dirty;
bool do_final_copy = false;
if (src_inode == dst_inode)
return -EINVAL;
if (ceph_snap(dst_inode) != CEPH_NOSNAP)
return -EROFS;
/*
* Some of the checks below will return -EOPNOTSUPP, which will force a
* fallback to the default VFS copy_file_range implementation. This is
* desirable in several cases (for ex, the 'len' is smaller than the
* size of the objects, or in cases where that would be more
* efficient).
*/
if ((src_ci->i_layout.stripe_unit != dst_ci->i_layout.stripe_unit) ||
(src_ci->i_layout.stripe_count != dst_ci->i_layout.stripe_count) ||
(src_ci->i_layout.object_size != dst_ci->i_layout.object_size))
return -EOPNOTSUPP;
if (len < src_ci->i_layout.object_size)
return -EOPNOTSUPP; /* no remote copy will be done */
prealloc_cf = ceph_alloc_cap_flush();
if (!prealloc_cf)
return -ENOMEM;
/* Start by sync'ing the source file */
ret = file_write_and_wait_range(src_file, src_off, (src_off + len));
if (ret < 0)
goto out;
/*
* We need FILE_WR caps for dst_ci and FILE_RD for src_ci as other
* clients may have dirty data in their caches. And OSDs know nothing
* about caps, so they can't safely do the remote object copies.
*/
err = get_rd_wr_caps(src_ci, (src_off + len), &src_got,
dst_ci, (dst_off + len), &dst_got);
if (err < 0) {
dout("get_rd_wr_caps returned %d\n", err);
ret = -EOPNOTSUPP;
goto out;
}
ret = is_file_size_ok(src_inode, dst_inode, src_off, dst_off, len);
if (ret < 0)
goto out_caps;
size = i_size_read(dst_inode);
endoff = dst_off + len;
/* Drop dst file cached pages */
ret = invalidate_inode_pages2_range(dst_inode->i_mapping,
dst_off >> PAGE_SHIFT,
endoff >> PAGE_SHIFT);
if (ret < 0) {
dout("Failed to invalidate inode pages (%zd)\n", ret);
ret = 0; /* XXX */
}
src_oloc.pool = src_ci->i_layout.pool_id;
src_oloc.pool_ns = ceph_try_get_string(src_ci->i_layout.pool_ns);
dst_oloc.pool = dst_ci->i_layout.pool_id;
dst_oloc.pool_ns = ceph_try_get_string(dst_ci->i_layout.pool_ns);
ceph_calc_file_object_mapping(&src_ci->i_layout, src_off,
src_ci->i_layout.object_size,
&src_objnum, &src_objoff, &src_objlen);
ceph_calc_file_object_mapping(&dst_ci->i_layout, dst_off,
dst_ci->i_layout.object_size,
&dst_objnum, &dst_objoff, &dst_objlen);
/* object-level offsets need to the same */
if (src_objoff != dst_objoff) {
ret = -EOPNOTSUPP;
goto out_caps;
}
/*
* Do a manual copy if the object offset isn't object aligned.
* 'src_objlen' contains the bytes left until the end of the object,
* starting at the src_off
*/
if (src_objoff) {
/*
* we need to temporarily drop all caps as we'll be calling
* {read,write}_iter, which will get caps again.
*/
put_rd_wr_caps(src_ci, src_got, dst_ci, dst_got);
ret = do_splice_direct(src_file, &src_off, dst_file,
&dst_off, src_objlen, flags);
if (ret < 0) {
dout("do_splice_direct returned %d\n", err);
goto out;
}
len -= ret;
err = get_rd_wr_caps(src_ci, (src_off + len),
&src_got, dst_ci,
(dst_off + len), &dst_got);
if (err < 0)
goto out;
err = is_file_size_ok(src_inode, dst_inode,
src_off, dst_off, len);
if (err < 0)
goto out_caps;
}
object_size = src_ci->i_layout.object_size;
while (len >= object_size) {
ceph_calc_file_object_mapping(&src_ci->i_layout, src_off,
object_size, &src_objnum,
&src_objoff, &src_objlen);
ceph_calc_file_object_mapping(&dst_ci->i_layout, dst_off,
object_size, &dst_objnum,
&dst_objoff, &dst_objlen);
ceph_oid_init(&src_oid);
ceph_oid_printf(&src_oid, "%llx.%08llx",
src_ci->i_vino.ino, src_objnum);
ceph_oid_init(&dst_oid);
ceph_oid_printf(&dst_oid, "%llx.%08llx",
dst_ci->i_vino.ino, dst_objnum);
/* Do an object remote copy */
err = ceph_osdc_copy_from(
&ceph_inode_to_client(src_inode)->client->osdc,
src_ci->i_vino.snap, 0,
&src_oid, &src_oloc,
CEPH_OSD_OP_FLAG_FADVISE_SEQUENTIAL |
CEPH_OSD_OP_FLAG_FADVISE_NOCACHE,
&dst_oid, &dst_oloc,
CEPH_OSD_OP_FLAG_FADVISE_SEQUENTIAL |
CEPH_OSD_OP_FLAG_FADVISE_DONTNEED, 0);
if (err) {
dout("ceph_osdc_copy_from returned %d\n", err);
if (!ret)
ret = err;
goto out_caps;
}
len -= object_size;
src_off += object_size;
dst_off += object_size;
ret += object_size;
}
if (len)
/* We still need one final local copy */
do_final_copy = true;
file_update_time(dst_file);
if (endoff > size) {
int caps_flags = 0;
/* Let the MDS know about dst file size change */
if (ceph_quota_is_max_bytes_approaching(dst_inode, endoff))
caps_flags |= CHECK_CAPS_NODELAY;
if (ceph_inode_set_size(dst_inode, endoff))
caps_flags |= CHECK_CAPS_AUTHONLY;
if (caps_flags)
ceph_check_caps(dst_ci, caps_flags, NULL);
}
/* Mark Fw dirty */
spin_lock(&dst_ci->i_ceph_lock);
dst_ci->i_inline_version = CEPH_INLINE_NONE;
dirty = __ceph_mark_dirty_caps(dst_ci, CEPH_CAP_FILE_WR, &prealloc_cf);
spin_unlock(&dst_ci->i_ceph_lock);
if (dirty)
__mark_inode_dirty(dst_inode, dirty);
out_caps:
put_rd_wr_caps(src_ci, src_got, dst_ci, dst_got);
if (do_final_copy) {
err = do_splice_direct(src_file, &src_off, dst_file,
&dst_off, len, flags);
if (err < 0) {
dout("do_splice_direct returned %d\n", err);
goto out;
}
len -= err;
ret += err;
}
out:
ceph_free_cap_flush(prealloc_cf);
return ret;
}
const struct file_operations ceph_file_fops = { const struct file_operations ceph_file_fops = {
.open = ceph_open, .open = ceph_open,
.release = ceph_release, .release = ceph_release,
...@@ -1810,5 +2102,5 @@ const struct file_operations ceph_file_fops = { ...@@ -1810,5 +2102,5 @@ const struct file_operations ceph_file_fops = {
.unlocked_ioctl = ceph_ioctl, .unlocked_ioctl = ceph_ioctl,
.compat_ioctl = ceph_ioctl, .compat_ioctl = ceph_ioctl,
.fallocate = ceph_fallocate, .fallocate = ceph_fallocate,
.copy_file_range = ceph_copy_file_range,
}; };
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